Hooboy thats a simple question with a LONG answer. But in short. An artificer from way fuckin back served as a vessel for something referred to as "Endless Answers" becoming a puppet for the world eater to do bidding through. Said artificer was a pupil of one of the first archwizards and that wizard set off the chain of events that would lead the artificer to sealing a pact with Endless Answers. For 40+ years the two feuded until the artificer was capable of fully bringing their host to the same plane. Unable to kill the beast, the wizard sacrificed themself to effectively convert the being into unaspected energy and bound it to the nearest tree (There is like an actual scientific reasoning for this but this is long enough as is LOL) The tree ended up draining a huge amount of ambient and underground energy from the world causing magic to slowly fade into obscurity. Years later the tree withered away and left behind 2 fruits with it. Fruits then became Morg and Reshimorg!